SUN-010 Efficacy of High Intensity Intermittent Training for Improving Cardio-Metabolic Health in Women with Polycystic Ovary Syndrome: A Pilot Study

Abstract

Polycystic ovary syndrome (PCOS) is a common and complex endocrinopathy with reproductive and metabolic manifestations, carrying a major health and economic burden. Exercise training has consistently been found improve clinical outcomes in women with PCOS, but shortfalls with exercise prescription are evident. Research suggests that high intensity intermittent exercise (HIIT) is feasible, well tolerated and enjoyable for people with or at risk of chronic disease and can address many of the shortfalls and barriers to exercise participation. To investigate the effects of high intensity exercise, twenty-four reproductive aged, overweight and obese, previously sedentary women with PCOS were recruited from the community and randomised to complete either 12 weeks of moderate intensity continuous cycling exercise (MOD; 50-60% of maximal heart rate [HRmax]; n=11) or HIIT (90-95% HRmax; n=13). All exercise was supervised by an exercise physiologist and completed 3 times per week on a cycle ergometer. Baseline and post testing measures consisted of peak oxygen consumption (VO2peak) determine by a graded maximal exercise test, insulin sensitivity determined by hyperinsulinaemic-euglycaemic clamp, body composition outcomes and anti-mullerian hormone (AMH). Enjoyment was also measured throughout the intervention using feeling scales. Significant improvements were seen for VO2peak after HIIT with an average increase of 5.6 ± 2.5 mL.kg-1.min-1 (P=0.013) and non-significant increases in the MOD group (3.4 ± 2.1 mL/kg/min; P=0.20). Body composition, fasting insulin and AMH values remained unchanged in both groups. Non-significant improvements in glucose infusion rate (3.3 ± 2.8 mg.lbmkg-1.min-1; P=0.06) and insulin sensitivity index (M-to-I ratio; 3.0 ± 3.8 mg.lbmkg-1.min-1[mU/I]-1 x 100; P=0.17) were found as a result of HIIT compared to no changes after moderate intensity exercise. Importantly, HIIT was also found to be more enjoyable than moderate intensity continuous exercise. The present study is the first to compare current exercise recommendations of moderate and vigorous intensities in women with PCOS. The results of this study provide preliminary validation of HIIT and should be considered for improving cardio-metabolic health in women with PCOS.